1. Field of the Invention
The present invention relates to a character recognition system for recognizing a character string read through, e.g., an optical character reading apparatus.
2. Description of the Related Art
Normally, a character string printed on a slip is read by an optical character reader (OCR), and the read character string is recognized in units of characters to be input to a computer. In this case, various character recognition techniques have been proposed, as described in U.S. Pat. No. 3,541,511, for example.
In such a character recognition system, when a handwritten character string is to be recognized, various problems are posed. For example, since handwritten characters have a variety of sizes, individual characters must be extracted from an input character string. In this case, when a handwritten character is a Chinese character, its left- and right-hand radicals may be extracted as separate character strings. For example, as shown in FIG. 1, if a character string " " is input, characters may be extracted like " ", " ", " ", " ", and so on, as shown in FIG. 2. As a result, a recognition result may become different from the input character string.
In a conventional system, recognition character candidates corresponding to characters are stored in a recognition result memory. A character candidate string of a character string to be recognized is generated using the character candidates stored in the recognition result memory, and is stored in a character candidate memory. The character candidate string is read out from the character candidate memory, and is collated with a character string of a dictionary word registered in a dictionary memory, thereby obtaining a recognition result.
A conventional character recognition system disclosed in Unscreened Japanese Patent Disclosure (Kokai) No. 61-160182; Y. KUROSAWA, Unscreened Date: Jul. 19, 1986, is known. In this character recognition system, since the recognition direction of characters is limited to one direction, if characters rotated through 180 degrees are input, they cannot be recognized.